deploy_mcp_server · Last Rock MCP: Risk & Policy

WHAT IT DOES

What deploy_mcp_server does on Last Rock MCP

AI agents invoke deploy_mcp_server to trigger actions in Last Rock MCP. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why deploy_mcp_server needs a policy

This tool executes infrastructure deployment operations on a remote platform (Fly.io), which is an irreversible operational action that affects live systems. While not destructive in the data-deletion sense, deployment triggers external execution with significant blast radius: misconfigured deployments could take down services, expose secrets, or corrupt application state.

From the tool's definition Tool description states it "Deploy[s] MCP server to Fly.io" with "state tracking, locks, and health checks." The emphasis "DO NOT use ssh_exec for deployments - always use this tool instead" indicates this triggers external operations (deployment to Fly.io)…

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

deploy_mcp_server Rate-limited

deploy_mcp_server stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "deploy_mcp_server": {
      "limits": [
        {
          "counter": "deploy_mcp_server_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Last Rock MCP, so you can run agents against it safely.

FAQ

Questions about deploy_mcp_server

What does the deploy_mcp_server tool do? +

Deploy MCP server to Fly.io with state tracking, locks, and health checks. DO NOT use ssh_exec for deployments - always use this tool instead. It is categorised as a Execute tool in the Last Rock MCP MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on deploy_mcp_server? +

Register the Last Rock MCP server in PolicyLayer and add a rule for deploy_mcp_server: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Last Rock MCP. Nothing to install.

What risk level is deploy_mcp_server? +

deploy_mcp_server is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit deploy_mcp_server? +

Yes. Add a rate_limit block to the deploy_mcp_server rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block deploy_mcp_server completely? +

Set action: deny in the PolicyLayer policy for deploy_mcp_server. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides deploy_mcp_server? +

deploy_mcp_server is provided by the Last Rock MCP server (itsablabla/lastrock-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.